Catalytically efficient beta-D-xylosidase from Selenomonas ruminantium (SXA) exhibits pK (a)s 5 and 7 (assigned to catalytic base, D14, and catalytic acid, E186) for k (cat)/K (m) with substrates 1,4-beta-D-xylobiose (X2) and 1,4-beta-D-xylotriose (X3). Catalytically inactive, dianionic SXA (D14(-)E186(-)) has threefold lower affinity than catalytically active, monoanionic SXA (D14(-)E186(H)) f...

For the synthesis of Mequinol (4-methoxy phenol), two acidic ionic liquids based on imidazolium cation (BMSIL and IMSIL) synthesized and characterized by FT-IR, 1H NMR, and CHNS analyses. Tan, the Baeyer–Villiger oxidation of para-anisaldehyde was studied with these ionic liquids, as the catalysts. The results showed that the BMSIL with more Brønsted acidic functions had higher c...

The catalytic performance of Ni-Al, Mg-Al, and Co-Ni LDHs as novel nanocatalysts was evaluated in the oxidation of toluene. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). The XRD and FTIR approved the structure and functional groups of the LDH, respectively. Also, the presence of cations with dif...

The well-known immologically active component of pneumococci, C-polysaccharide, is a teichoic acid that can be isolated from the cell walls and purified by Sephadex and ionexchange chromatography. Further details of the structure of C-teichoic acid were established by chemical degradation, including hydrolysis in acid and alkali, treatment with HF, periodate oxidation and methylation. In additi...

In recent years, there has been considerable interest in studies of catalytic metal clusters in metalloproteins based on Density Functional Theory (DFT) quantum mechanics/molecular mechanics (QM/MM) hybrid methods. These methods explicitly include the perturbational influence of the surrounding protein environment on the structural/functional properties of the catalytic centers. In conjunction ...

Anomeric C–H bond activation is an unsolved long-standing synthetic challenge. Herein, we report a diastereoselective Pd-catalyzed anomeric C(sp3)–H methodology that allows the synthesis of elusive C-(hetero)aryl glycosides with exclusive α-selectivity.

The redox properties of sulfite ion has been examind using cyclic voltammetry in acetonitrile solvent at the surface of gold, pelatin and glassy carbon electrodes. It has bben found tha, sulfite ion exhibits two electron oxidation peak with EC’ mechanism. A novel chemically modified electrode containing Prussian blue complex and multi wall carbon nanotubes (MWCNs) was achieved on the surface of...

Introduction Aerobic catalytic oxidation is much more environmentally friendly than oxidation using stoichiometric oxidants. The Pd(OAc)2/pyridine system is active for the catalytic oxidation of primary and secondary alcohols to aldehydes and ketones, which are valuable for fine chemicals synthesis. Pyridine stabilizes the monomeric Pd complex and promotes its aerobic reoxidation to Pd prior to...

In this study, 1,2-dichlorobenzene (DCB), an important precursor of PCDDs and PCDFs, was chosen as a suitable model compound for the catalyzed deep oxidation of dioxin. The recently developed mesoporous materials from zeolites (MMZ) were used for the first time as a support for an oxidation catalyst. The catalytic oxidation of 1,2-dichlorobenzene over Pt/MMZ was carried out, and the catalytic a...